Sprinklers in high rise flats?

[Guest FRA Bob]

We are retro fitting sprinklers to high rise flats, should they be in the flats or in the communal areas?

[AnthonyB]

Do you not have access to a competent advisor? That's a massive undertaking without having been told what, where and how to do it.

The risk is in the flats and sprinkler provision is to each flat in order to protect the common areas, adjoining flats & to some extent the occupants.

Each flat usually has a system installed to BS 9251: 2005 – Sprinkler Systems for Residential and Domestic Occupancies, although this standard covers up to 20m fire engineers can usually mitigate use at higher heights and common supply sprinkler booster pumps are often installed to support this.

For retrofitting a lot of mist based systems are available that are cheap,easy to install, have less issues with water supplies and the need for booster pumps and are still BS compliant

Common circulation areas don't need cover, it's not uncommon to cover certain ancillary accommodation like bin stores though.

[EthiXL]

AnthonyB is right but the standards have moved on with BS9251 updated in 2014.  For a residential block of flats a category 2 system is required (the categories define the design discharge density and sprinkler head coverage).  The system can be fed directly from the mains, by booster pump or by tank but all this is dictated by a number of different criteria.  A 9251 system may require further consultation with the authority having jurisdiction where the building is over 45 metres in height, complex, buildings with an atria, vulnerable individuals etc.

On the practical side there is always resistance, particularly from those that may have to burden the cost or from those that worry about the aesthetics to their home or the cost of a faulty system if their property floods (statistically rare even with a wet system).  The two most important things are the correct calculations/designs from a competent company and winning the hearts and minds of residents.

 

Good luck.